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    <title>Document</title>
    <style>
        .box1{
            display: none;
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        div:hover ul{
            display: block;
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        div:hover span{
            color: pink;
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        a{
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    <div>
        <a href="#"><span>军事密码</span></a>
        <ul class="box1">
            <li>3456</li>
            <li>3453</li>
            <li>2455</li>

        </ul>
    </div>
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